carotene

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carotene

(kâr`ətēn'), long-chained, unsaturated hydrocarbon found as a pigment in many higher plants, particularly carrots, sweet potatoes, and leafy vegetables. Carotene is thought to assist in trapping light energy for photosynthesisphotosynthesis
, process in which green plants, algae, and cyanobacteria utilize the energy of sunlight to manufacture carbohydrates from carbon dioxide and water in the presence of chlorophyll. Some of the plants that lack chlorophyll, e.g.
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 or to aid in chemical reduction. It is important in animal biology as the main dietary source of vitamin A (see vitaminvitamin,
group of organic substances that are required in the diet of humans and animals for normal growth, maintenance of life, and normal reproduction. Vitamins act as catalysts; very often either the vitamins themselves are coenzymes, or they form integral parts of coenzymes.
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), which is produced by splitting one molecule of carotene into two molecules of vitamin A. Carotene that is thus converted is called provitamin A. This reaction occurs in either the liver or intestinal wall. The absorption of dietary carotene is dependent on the action of bile. Its absorption is less efficient than that of vitamin A. High intake of dietary carotene is being studied for its disease prevention potential. Carotenes are the simplest of a group of natural pigments called carotenoids, of which there are more than 600.
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carotene

[′kar·ə‚tēn]
(biochemistry)
C40H56 Any of several red, crystalline, carotenoid hydrocarbon pigments occurring widely in nature, convertible in the animal body to vitamin A, and characterized by preferential solubility in petroleum ether. Also known as carotin.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

carotene

, carotin
any of four orange-red isomers of an unsaturated hydrocarbon present in many plants (β-carotene is the orange pigment of carrots) and converted to vitamin A in the liver. Formula: C40H56
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
References in periodicals archive ?
Direct sun drying was accompanied with direct exposure to sun light and relatively increased temperature which were responsible for deterioration of total carotenoids and provitamin A contents (Table 1).
Retention of higher nutritional components like provitamin A carotenoids is essential to get the nutritional benefits and prevent malnutrition against vitamin A deficiency.
Unsurprisingly, the type of processing influences the level of provitamin A retention in OSP.
Provitamin A carotenoid degradation occurs during storage due to oxygen and temperature conditions that chemically oxidize the trans-beta-carotene [14].
Carotenoid Identificatioin Parameters Retention time (min) 1 Lutein 11.9-12.4 2 [alpha]-cryptoxanthin / Zeinoxanthin 18.5-19.4 3 [beta]-cryptoxanthin 19.4-20.3 4 [alpha]-carotene 28.4-29.4 5 Trans-[beta]-carotene 29.9-30.9 6 Cis-[beta]-carotene 31.5-32.7 -- Total carotenoids -- -- Provitamin A (RAE/100g) -- Peak no.
Stored vitamin A will help meet your needs when intake of provitamin A carotenoids or vitamin A is low (19, 20).
The IOM states that "B-carotene supplements are not advisable for the general population", although they also state that this advice "does not pertain to the possible use of supplemental B-carotene as a provitamin A source for the prevention of vitamin A deficiency in populations with inadequate vitamin A nutriture" (13).
Similarly, HarvestPlus and its partners have developed analytical methods for provitamin A carotenoid analysis in sweet potato, cassava, maize, and banana.
Conventionally bred orange sweet potato (OSP) containing provitamin A was the first biofortified crop developed and released by the International Potato Center (CIP), HarvestPlus, and its partners.
Furthermore, they were able to turn a white-rooted cassava cultivar into a yellow-rooted plant that accumulates beta-carotene (provitamin A) using a transgenic approach that increased the enzyme phytoene synthase in the root.
This chapter provides an overview of: (i) the policy background and justification for developing, introducing, and scaling up use of provitamin A varieties in Zambia, (ii) an overview of crop development activities, (iii) the strategy and experience-to-date with dissemination of orange maize, and (iv) past and planned efforts to measure impact.
This chapter provides an overview of (i) the policy background and justification for developing, introducing, and scaling up use of provitamin A varieties in Nigeria, (ii) crop development activities, (iii) the strategy and experience-to-date with dissemination of biofortified varieties of cassava, and (iv) past and planned efforts to measure impact.